Chemiluminescence is the emission of light as a result of a chemical reaction. There may also be limited emission of heat during the chemical reaction. Typically, a reaction beginning with reactants A and B, with an excited intermediate, yields products and light. Typically, there are many applications that use chemiluminescence. For example, chemiluminescence is used in gas analysis, analysis of inorganic and/or organic species, detection and assay of biomolecules, DNA sequencing, lighting objects, and children's toys.